Current fuses that blow by self-heating to cut off a current path when current exceeding a rating thereof flows are in conventional use. A typically provided current fuse is made from a low melting point metal such as Pb solder. Examples of commonly used fuse elements include a holder-fixed fuse in which solder is enclosed in a glass tube, a chip fuse in which an Ag electrode is printed on the surface of a ceramic substrate, and a screw-fastened or plug fuse in which part of a copper electrode is narrowed and assembled into a plastic case.